Conventional beam deflection beam techniques usually rely upon the electronic control of either a mechanical device, such as a mirror, or an electro-optic device. Because of inertial constraints and the other problems associated with the mechanical approaches, optical techniques have shown promise to be to be more satisfactory.
Known techniques for optical deflection use optical or acoustic gratings so that beam deflection is accomplished by changing the grating spacing, by moving one of the grating beams or by changing the wavelength of the beam which influences a crystal to change its induced grating. The reliabilities of a number of the contemporary schemes, since they may partially rely on mechanical devices, often are compromised particularly in the case of higher frequency applications, since the associated electromechanical and electronic devices may not fulfill all expectations. As a consequence, the hoped-for optical deflection precision is not attained.
A number of thermal lensing techniques for purposes other than this inventive concept are well known which rely on various phenomena to focus beams but usually deleterious side effects occur, such as damage to some elements and beam distortions.
Thus, there exists a continuing need in the state of the art for an optical deflection scheme that avoids the use of associated electronic or mechanical devices to accomplish a signal beam deflection at relatively large deflection angles.